Process of making wrought iron



.I. ASTON.

PROCESS OF MAKING WROUGHT IRON.

APPLICATION FILED APR. 24, 1920.

Patented Apr. 18, 1922.

2 SHEETS-SHEET I.

I. ASTON.

PROCESS OF MAKING WROUGHT IRON.

APPLICATION FILED APR. 24, I920.

Patented Apr. 18, 1922.

2 SHEETSSHEET 2.

UNAITED'STATES PATENT oFFrcEp JAMES ASTON, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO A. M. BYERS COM- IPANY, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION OF I'ENNSYLVANIA'.

PROCESS OF MAKING WROUGHT I-RON. I

Specification of Letters Patent. Patented A1 18 1922 I Application filed April 24, 1920. Serial No. 376,388.

Making \Vrought Iron, of which the follow is a full, clear, and exact description,

in reference being. had to the accompanying drawings, forming part of this specification, in which' Figure 1 is a diagrammatic view showing one form of apparatus for carrying out my invention;

Figure 2 is' a similar view showing another form of apparatus therefor; and

Figure 3 is a plan ,view of one of the molds shown in Figure 2. The present invention relates to an improvement upon my process of making wrought iron by pouring the molten product of a steel-making process into a slag bath of the proper chemical and physical characteristics, the metal being granulated or comminuted and mixed with a slag to form a coherent-mass or ball below the surface of the slag bath.

In the form described and claimed in my copending application Serial No. 376,247, dated April 24, 1920, the molten metal is poured into a ladle containing the proper slag, the coherent mass or ball forming in the bottom portion of the ladle or slag re c'eptacle. The surplus slag is then removed,

and the ball taken out for compressing.

In my present process, I compress the coherent mass or ball of comminuted slag and metal within the mold or receptacle in which the mass is formed; I thus avoid the labor, expense and delay of removing the mass for the purpose of compression, the surplus slag being, of course, preferably removed prior to compression. In carrying out this improved process, the metal may either be comminuted in the air as it-is dropped into the slag bath, as set forth in the preferred form described in my U. S. Patent No. 1,370,622, granted March 8, 1921, for Method of making wrought iron, or the metal may be comminuted in the slag bath by pouring a stream of the molten metal directly into the bath as in my copending application, Serial No. 376,247, filed April 24, 1920; for Methods of making wrought iron.

In the drawings, referring to the form of Figure 1, 2 represents a slag-heating furnace in which. a puddling slag may be prepared. These slags are essentially iron silicates containing ferric 0X1d6, ferrous oxide, sllica, phosphorlc oxide and manganese ox de "with some alumina. The ferris oxide should be kept low as it has a high oxidizing power; in contact With-metallic iron, the reaction produclng ferrous oxide from the iron.

Consequently, I preferably employ carbon on or in the slag bath which may be in the form of crushed coke, carbon, electrodes, etc, to keep the percentage of ferric oxide low and to reduce the same to some extent.

This furnace is preferably a tilting furnacethe molten slagbeing fed through a spout 3, for example, into cast iron molds 4, resting on cast iron stools 0, carried on trucks or wheels 6, resting on a track 7. The coke or other carbon blanket over the slag will, of.

course,be held back when the slag is poured into successive molds.

These molds are preferably of large size, being of generally rectangular form in cross section and preferably elongated in one direction so that when the ball is compressed, it will' be longer in a horizontal direction than in height. The molds are preferably provided with stripping lugs 7 and are preferably open at top and bottom. The stools are preferably provided with a spout or lip portion 8, at one side, as shown in side elevation at the center of the figure, so that when the mold body is lifted, the slag will be directed into a slag buggy or receptacle.

After a suitable amount of slag suflicient to cover the coherent mass or ball is fed into one of the molds, the mold is pushed from the position A to the position B underneath a ladle9, containing the molten product of a steel-making operation. The steel may be made in a Bessemer converter, an openhearth furnace, an electric furnace or any other desired apparatus for making molten steel. The ladle is shown as a bottom-pour ladle, and the steel is fed therefrom down through the open air into the slag bath inthe mold. The ladle may be carried by an oughly intermingled with the slag. This steel-making furnace or taking the steelmaking furnace to ,the desired position.

The mold is of proper size and sufiicient steel is fed therein to make a ball, preferably of a weight of two thousand pounds or more,

so that after compressing the ball may be rolled directly into slabs or billets without repiling.

After the ball-forming operation, the car maybe moved along on the track to the position C, and the mold lifted by a suitable apparatus having depending straps or lTdoks 10 to engage the mold lugs, as shown. The hot slag will usually chill and form a crust at the bottom of the mold body, so that when the mold is lifted slightly, a hook or tool may be inserted to break this crust and allow the surplus slag to drain out of the mold on to the stand, and thence flow from the stand over the pouring lip into the wheeled slag receptacle 11, movable on track 12. After the surplus slag is removed, the mold may be lowered on the stand and the car moved along to a position D, between the plungers 13 and 14 of a press. The plunger 14 is moved up between the track rails to lift the car or stand slightly, and the plunger 13 is then forced down to compress the coherent mass or ball of mixed metaland slag into a ball which preferably has its longest dimension at right angles to the sheet of the drawing and extending horizontally;

After this operation, the car may be moved along on the track to the position E, where the mold, which is preferably internally tapered somewhat from the bottom toward the top, is stripped by means of a stripper, indicated at 15 and engaging the mold lugs. The compressed and shaped bloom maythen be taken to a blooming mill and rolled at the same heat into slabs or billets; or the compressed bloom may be taken to 'asoaking pit for holding and equalizing its heat or for being further heated prior to being rolled into billets. The slabs or billets may then be stored and passed through a continuous heating furnace to a skelp mill where they are rolled directly into skelp or to another mill to give any desired product, such as wire, sheets, etc.

'I have found that with a large ball of this form, there is thorough distribution and dissemination of the slag through the rolled mass, so that no cutting and repiling of muck bar is necessary as in the usual puddling operation.

The temperature of the slag is preferably sufficiently below that of the molten metal entering it, so that in the adjustment of the equilibrium of temperature between the slag and the metal, the granulated iron will solidify to a spongy mass or ballby reason of its being at the welding heat necessary silica. The forming of the ball introduces some iron oxide into the slag, thereby diluting the iron silicates. therefore to keep the slag of the proper physical and chemical characteristics, the slag which is returned to the'bath should be revivified by the silica addition. T he formation of ferric oxide in the slag may be retarded or prevented by keeping a reducing atmosphere instead of an oxidizing atmosphere in the slag-melting furnace.

In Figure 2, I show another form of apparatus generally similar to that of Figure 1. similar parts being designated by similar numerals with the letter a attached. In this form, the mold 4 is a tilting mold, the stand 5 having standards 15, to which the mold is pivoted at one side by trunnions 16. On the-opposite side of the mold is a lifting lug or lugs 17.

In this form, when the car reaches station C, the mold is operated by a suitable device 18, engaging the mold lug 17, so that the surplus slag is poured from the top of the mold into the slag receptacle 11. The mold may then be allowed to swing back to normal position and the car is run on to .a truck 19. movable on a track 20, extending at an angle to the track 7*, and having a section 7 of the track 7 carried thereon. \Vhen this truck 19 receives the car with the mold containing the ball, the truck is moved sidewise to another point between the plungers 13 and 14 of a press. and themold is tilted into the horizontal position so that the mass may be compressed. as shown at D. After compression, the bloom may be pushed out to the larger end of the tapered mold and taken to the soaking pit or to the blooming mill, as before described.

In both forms, asuccession of cars with molds thereon is employed, these cars in the preferred form shown being moved to the different positions where the successive steps are carried out. It will be understood. however, that the steps or some of them may be carried out in one position of the mold without moving it to separate stations.

Instead of pouring the surplus slag from the molds into a slag receptacle, it'may be poured from the mold back into the slagmelting furnace,-with suitable silica addi- If this is done,

tion torevivify it, or it may be poured into another mold, preferably with the same silica addition, to form or partly form the slag bath for the next ball.

Many changes may be made in the apparatus employed, as well as in the steps of my process, without departing from my invention. YVithin the scope of my claims, parts of my complete process forming'subprocesses may be used, without departing from my invention. The molds or shaping receptacles may be changed in form or shape as well as material.

I claim: r

1; The method of making Wrought iron, consisting in forming within a receptacle a coherent mass or ball from the granulated substantially slagless product of a steel-- making process and a slag having the proper physical and chemical characteristics for making wrought iron, and compressing the said mass within the receptacle; substantially as described.

2. The method ofproducing wrought iron, consisting in forming in a receptacle and below the surface of a slag bath therein having the proper physical and chemical characteristics for making wrought iron, a co- 'herent mass of the granulated substantially slagless product of a steel-making process and said slag, removing the surplus slag,

and compressing the coherent mass Within said receptacle, substantially as described. 3. The process of making wrought iron,

consisting in feeding into a receptacle con-' taining-a slag bath of the proper physical and chemical characteristics for making wrought iron the substantially slagless product of a steel-making process, forming a' taining a slag bath of the proper physical and chemical characteristics for making wrought iron the substantially slagless product of a steel-making process, forming a coherent mass or ball of mixed slag and granulated metal below the surface of said bath, removing the surplus slag, and compressing the mass within said receptacle, substantially as described.

5. The method of producing wrou ht iron, consisting in feeding the product 0 a steelmaking process into a shaping receptacle containing a bath of slag of the proper characteristics to make wrought iron, forming a large coherent mass of metal and slag therein, compressing the same in'the receptacle, and then removing the compressed bloom and rolling it directly into slabs or billets, substantially as described.

6. The method of making wrought iron,

consisting of forming within a receptacle a coherent mass of metal and slag of such a size as not to require repiling, compressing it in the receptacle, and then removing and rolling the same, substantially as described. 7. The method of making Wrought iron, consisting in forming a mixed mass of slag and metal within a receptacle having open ends, compressing the mass therein, and then removing the compressed mass fromthe receptacle, substantially as described.

8. The method of making wrought iron,

consisting in forming a mixed mass of slag and metal within a receptacle having open ends, removing the surplus slag, compressing ing n the successive receptacles a coherent mass of mixed metal and slag, removing the surplus slag, compresslng the masses in the receptacles, and removing them successively,

substantially as described.

10. In the method of making wrought iron, the steps consisting in forming within a receptacle having diverging walls a coherent mixed mass of slag and metal, com-.

pressing the same therein, and removin the compressed mass, substantially as described. 11. In the method of making Wrought iron, the steps consisting in forming within" a receptacle having diverging walls a coherent mixed mass of slag and metal, compressing the same therein, removing the compressed mass. and rolling it directly into slabs or billets without repiling, substantially as described.

12. In the method of making wrought iron, the steps consisting of forming within a receptacle a mixed mass of metal and slag, removing the surplus slag. revivifying and r'e-using said slag, compressing the mass within the receptacle, and removing it therefrom. substantially as described.

'13. .In the method of making wrought iron, the steps consisting of forming within a receptacle a mixed mass of slag and metal,

compressing the same therein, removing the surplus slag, re-using said slag, and remov- I ing the mass from the receptacle, substantially as described.

14. In the method of making wrought iron, the steps consisting of forming within a receptacle a mixed mass of metal and slag of such a size as not to require repiling, re-' moving the surplus slag, compressing the mixed mass within the receptacle, and then removing and rolling the same, substantially as described.

'15. In the method of making wrought iron, the steps consisting of providing a bath of slag with the proper characteristics for making wrought iron, feeding a portion of the bath into a receptacle, forming within said receptacle and below the surface of the slag bath a coherent mass or ball of metal and slag, removing the surplus slag, and re-using it, compressing the mass within the receptacle, removing it therefrom, and rolling the same. substantially as described.

16. In the method of making wrought iron. the steps consisting of maintaining a molten slag bath of the proper characteristics for making wrought iron, preventing or retarding the formation of ferric oxide in the bath, feeding a portion of the bath into a receptacle, feeding molten steel into the slag bath, and forming a mixed mass of granulated metal and slag therein, and compressing the mass within the receptacle, substantially as described.

17. in the method of making wrought iron. the steps consisting of maintaining a molten slag bath of the proper characteristics for making wrought iron. preventing or retarding the formation of ferric oxide in the bath, feeding a portion of the bath into a receptacle, feeding molten steel into the slag bath and forming a mixed mass of granulated metal and slag therein, compressing the mass within the receptacle, removing the surplusslag, and. removing and rolling the compressed mass, substantially as de-' scribed.

18. In the method of making wrought iron, the steps consisting of feeding molten 'of thebaths coherent masses of mixed metal and slag, compressing the said masses, removing the surplus slag and rolling the masses, substantially as described.

19. In the method of making wrought iron, the steps consisting of forming within a receptacle a coherent mass of slag and metal, removing the surplus slag, revivifying thesurplus slag by adding silica, compressing the mass within the receptacle, and rolling it, substantially as described.

' 20. A compacted spongy mass of wrought iron formedof the granulated product of a steel-making process. mixed with slag of wrought iron characteristics, said mass being compressed within and to the shape of the receptacle in which the mixture is formed, substantially as described.

21. A compacted spongy mass of wrought iron formed of the granulated product of a steel-making process, mixed with slag of wrought iron characteristics, said mass being compressed within and to the shape of the receptacle in which the'mixture is formed and being of sufficient size to be rolled direct into slabs or billets without cutting and repiling, substantially as described.

In testimony whereof, I have hereunto set my hand."

JAMES ASTON. 

